CAMPAIGN FINANCE REFORM suffered its second body blow in as many days last week when the Supreme Court ruled that political parties can spend as much as they like in congressional races so long as they act "independently" of actual candidates.

This could open the door wider to the vast sums of money flooding into the political process. It put the court ever closer to the view that First Amendment protection of free speech may, in the end, block efforts to limit the power of well-financed special interests.

Coming just after the Senate's failure to ban "soft money" and contributions from political action committees, the court now faces a case which appears to be a lose-lose proposition for reform advocates. It might either let stand a Missouri decision that a $300 limit on contributions is unconstitutional or it could take up the case and pursue the trend toward the collapse of all controls on political spending.

In 1976, the court banned limits on campaign spending but permitted limits on campaign contributions. The latter controls are now in jeopardy since four members of the court -- one short of a majority -- are now on record as saying such limits infringe free speech.

Republican campaign committees in command of fatter coffers than the Democrats vow to push their advantage to the hilt. They figure any moves by the Federal Election Commission to put a strict interpretation on what constitutes "independent" spending by the parties on congressional campaigns cannot be finally adjudicated until long after this year's political races are history. Democratic campaign committees are left to decry "fat cat" spending even though they, too, have an institutional interest in looser federal controls, particularly on the content of political TV ads.

A measure of Democratic disarray can be seen in Senate minority leader Tom Daschle's call for a constitutional amendment to allow campaign finance controls since the court decision made legislative reforms like those rejected last week more difficult. This is a bad idea, opposed by other pro-reform Democratic senators, because it would clutter up the Constitution and encounter insurmountable obstacles on the road to ratification. As one Common Cause lawyer put it, "The sky might not be falling but it's dropped a bit." Indeed.